1. Heat a grill pan over medium-high heat. Combine 1 teaspoon oil, 1/4 teaspoon salt, chipotle chile powder, and black pepper; rub evenly over steaks. Add steaks to pan; cook 4 minutes on each side or until desired degree of doneness. Let stand 10 minutes. Cut steaks diagonally across the grain into thin slices.
2. Combine remaining 4 teaspoons oil, remaining 1/4 teaspoon salt, juice, and next 4 ingredients (through honey) in a large bowl, stirring with a whisk. Stir in quinoa, beans, bell pepper, cilantro, green onions, and spinach; toss to coat. Sprinkle with feta. Divide quinoa mixture evenly among 4 shallow bowls; top evenly with steak and avocado.